Final answer:
Mrs. Altoonian sends Vahan away because someone named Krogstad had come to their house and requested her help. She gives Vahan a warning not to mention the stranger man to anyone.
Step-by-step explanation:
Mrs. Altoonian sends Vahan away because someone named Krogstad had come to their house and asked her to say a good word for him. Mrs. Altoonian had promised Krogstad that she would speak to her husband, but she didn't want her husband to know about it. She gave Vahan a warning not to mention the stranger man to anyone, not even to his father.